Support for an image-receiving material for the silver salt diffusion transfer process

ABSTRACT

A support for an image-receiving material for the silver salt diffusion transfer process having on a paper base, in order, a polyolefin resin layer and a polyvinyl butyral layer containing a fluorescent brightening agent, is disclosed.

nited States Patent 11 1 [111 3,776,761 Kato et a1. Dec. 4, 1973 SUPPORT FOR AN IMAGE-RECEIVING MATERIAL FOR THE SILVER SALT [56] References Cited DIFFUSION TRANSFER PROCESS UNITED STATES PATENTS [75] Inventors: Kazunobu K3); Kinji ()hkubo, both 3,312,549 4/1967 Salminen et a1. .1 96/3 f saitama, Japan 3,592,645 7/ 1971 Weyerts et a] 96/3 2,522,771 9/1950 Barnes 96/93 [73] Assignee: Fuji Photo Film Co., Ltd., Minami, 2,819,164 1/1958 Boersma 96/93 Ashigara-shi, Kanagawa, Japan [22] Filed: Apr. 21, 1972 Primary Examiner-Norman G. Torchin Appl. No.: 246,402

Foreign Application Priority Data Assistant Examiner-John L. Goodrow AttorneyRichard C. Sughrue et a1.

[5 7] ABSTRACT A support for an image-receiving material for the silver salt diffusion transfer process having on a paper base, in order, a polyolefin resin layer and a polyvinyl butyral layer containing a fluorescent brightening agent, is disclosed.

8 Claims, No Drawings 1 SUPPORT FOR AN IMAGE-RECEIVING MATERIAL FOR THE SILVER SALT DIFFUSION TRANSFER PROCESS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support for an image-receiving material for the silver salt diffusion transfer process.

2. Description of the Prior Art The diffusion transferphotography making use of silver salts such as silver halide has heretofore been known. In such photography, the photographic lightsensitive material prepared by dispersing fine particles of a light-sensitive silver salt such as a silver halide in a hydrophilic binder such as gelatin, etc., and coating it on a support, is imagewise exposed, then'placed in contact with a processing solution containing a developer. In this process, the exposed silver halide contained in the light-sensitive layer is reduced (or developed) to silver. When, simultaneously or subsequently, the light-sensitive material is treated with a water soluble silver halide complexing agent, the unexposed silver halide reacts with the complexing agent to form a water soluble silver complex.

On this occasion, when an image-receiving material having a layer containing a substance (development nuclei) which catalyze this water soluble silver complex-reducing reaction, or silver-depositing nuclei dispersed in a hydrophilic binder, is placed in contact with the light-sensitive layer, the silver complex produced in the light-sensitive layer diffuses from the light-sensitive and (3) the whiteness thereof should be high. When the water-proof properties are lost, the developer will penetrate into the support resulting in stains and fading the image formed thereon. A rough surface would produce irregularities in the density of the positive print, and a low whiteness would detract from the beauty of the image.

' In U.S. Pat. No. 2,789,054 use is described of a support having a cellulose acetate layer and a polyvinyl acetal layer in order on a baryta paper for an imagereceiving material for the silver salt diffusion transfer process. In thisprocess, the developer does not penetrate into the baryta layeror the paper base layer on developing, and hence the staining caused by the developer or any fading of the image is improved. However, it is difficult to provide specular luster by uniformly coating cellulose 'acetate or polyvinyl alcohol on the baryta paper. Generally, an extra process step of forcedly making the surface smooth by passing the paper several times through a super calender to heat and compress is required.

In British Pat. No. 1,148,174, use is described of a support prepared by laminating a polyolefin layer containing titanium oxide and a fluorescent brightening agent, on a paper base, and providing the polyolefinic layer with a hydrophilic property using a corona discharge process, as a support for an image-receiving material for the silver salt diffusion transfer process. Polyolefins, especially polyethylene and polypropylene, are

layer to the image-receiving layer'together with the processing solution, and is reduced to silver by the action of the developement nuclei in the image-receiving layer.

That is, over all, animage is formed on the imagemetal sulfides which are slightly soluble in water, metal selenides, heavy metals or colloidal noble metals are 7 usually used. The se agents 'are'dispersed ina high molecular weight material such aslgelatin, polyvinyl'alc'ohol, etc., intolwhich an alkaline solution can permeate,

' and the resulting disperson is coated on a support, such a paperyfilm, metal plate, etc., to prepare an imagereceiving material;

An image-receiving material containing silverdepositing nuclei with especially high activity is useful as a photographic material for high speed silver salt diffusion transfer photography. In U.S. Pat. No. 2,698,237, it is described that silver-depositing nuclei having an especially high activity can be obtained by mixing a water-soluble metal salt with a water-soluble sulfide in an aqueous dispersion of an especially fine silicon dioxide to prepare a precipitate 'of a waterinsoluble metal sulfide (which functions as silv'erdepositing nuclei). The aqueous dispersion of the silicon dioxide containing silver-depositing nuclei obtained in this way is coated on a support sheet and dried to obtain an image-receiving material, from which positive prints with a good image quality can be obtained.

As is described above, for the support for the imagereceiving material, it is required that l the support be water-proof, (2) the surface thereof should be smooth superior to cellulose acetate in that they are highly water-impermeable and stretch only to a small extent on heating. However, in the case of a polyethyleneor a polypropylene-laminated paper, it is difficult to increase the whiteness thereof even by the addition of a fluorescent brightening agent to the resin. In general, polyethylene or polypropylene is laminated on a sheet ofpaper by melt extrusion coating, but, those fluorescent brightening agents which can resist this melting temperature have such an insufficient brightening effectthat is difficult to obtain the whiteness necessary for a support for an image-receiving material for the silver salt diffusion transfer process. In addition, the surface treated with a" corona discharge will again become hydrophobieon aging, and hence it will become diffi cultto coat an image-receiving layer thereon.

An object of this invention is to provide a novel photographic support.

Another object is to provide a support especially suitable for an image-receiving material for the silver salt diffusion transfer process.

Another object is to provide a water-proof and'lustered support for an image-receiving material for the silver salt diffusiontransfer process.

Another .objectlis to provide a support having high storage stability for an image-receiving material for the silver salt diffusion transfer process.

A further object is to provide a support having a high whiteness for an image-receiving material for the silver salt diffusion transfer process.

SUMMARY OF THE INVENTION The inventors have made efforts to develop a support that serves such purposes and, as the result, have invented the following support.

That is, it is a support for an image-receiving material for the silver salt diffusion transfer process having, in order, a polyolefin resin layer and a polyvinyl butyral resin layer containing a fluoresent brightening agent thereon on a paper base.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyolefln resin layer in this invention is as a major component composed of polyolefin such as polyethylene. polypropylene, copolymers of ethylene and propylene etc. which are film-forming, adhesive to a sheet of paper and are water-proof. All types of polyethylene, polypropylene and copolymers are suitable. Generally, those having an average molecular weight ranging from about 10,000 to 100,000 are preferred. Where copolymers of ethylene and propylene are'used, those having a propylene content ranging from about 0.1 to 30 molar percent are preferred.

If desired, white pigments such as titanium dioxide, zinc oxide, zinc sulfide, lithopone, etc., a plasticizer, bluing dyes may be incorporated therein. The polyolefin resin layer is usually coated using a melt extrusion method. The polyolefin layer should be coated in a thickness necessary to maintain the water-proof property and the luster of the surface thereof, and, usually is in a thickness of more than 5 microns after drying.

The polyvinyl butyral layer is coated on the polyolefin layer usually as a solution for example as a solution of the polyvinyl butyral in a solvent such as benzene, toluene, chloroform, ethylene glycol mono butyl ether, n-butanol, ethyl acetate, methyl acetate, xylene, methanol, ethylene glycol mono methyl ether, cyclohexanone, o-dichlorobenzene, diacetone alcohol, dioxane, glacial acetic acid, mono chlorobenzene, solvent naphtha, cresylic acid, methylbutanol, methylpentanol, and the like. The polyvinyl butyral layer should be coated in a thickness necessary to obtain sufficient whiteness and, usually in a thickness of more than 0.5 micron. If the polyvinyl butyral layer is coated in a thickness thinner than 0.5 micron, sufficient whiteness in the composite support cannot be obtained.

Further a thick resin layer, i.e., the thickness of the resin layer formed of the polyolefin resin layer and the polyvinyl butyral resin layer does not cause any deleterious effects on the its photographic properties. However, too thick of a coating is not preferred because it increases the total thickness of the support, makes the support heavy and consumes extra polyolefin, polyvinyl butyral and solvent, and hence the production costs are increased. The polyolefin layer and the polyvinyl butyral layer are suitably coated in a thickness of less than about 0.1 mm and about 0.05 mm respectively.

Suitable fluorescent brightening agents which can be contained in the polyvinyl butyral layer are those which are soluble in organic solvents for example, alcohols such as methanol, ethanol, propanol, butanol, etc.; ketones such as acetone, ethyl methyl ketone, etc.; esters such as methyl acetate, ethyl acetate, etc.; ethers such as ethylene glycol mono methyl ether, ethylene glycol mono ethyl ether, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, etc.; and aliphatic hydrocarbons such as chloroform, cyclohexanone, tetrachloromethane, methylene chloride, etc.. Many fluorescent brightening agents can be used in the invention and the invention is not limited to any particular fluorescent brightening agent. However, the inventors have found that the following fluorescent brightening agents brin about preferehlel wh C.l. Fluorescent Brightening Agent 4 Calcofluor Yellow HEB (Trade name, made by American Cyanamid Co.)

C.I. Fluorescent Brightening Agent 57 Uvitex W (Trade name, made by ClBA Ltd.)

C.l. Fluorescent Brightening Agent 69 Leucophor DC (Trade name, made by Sandoz Ltd.)

C.l. Fluorescent Brightening Agent 70 Tinopal PCR (Trade name, made by Geigy J.R., A.G.)

C.I. Fluorescent Brightening Agent 72 Tinopal E (Trade name, made by Geigy J.R., A.G.)

C.l. Fluorescent Brightening Agent 73 Blancol SS (Trade name, made by L.B. Holliday & Co., Ltd.)

C.l. Fluorescent Brightening Agent 76 Fluorol OB (Trade name, made by General Aniline & Film Corp.)

C.l. Fluorescent Brightening Agent 9| Kayalight B (Trade name, made by Nippon Kayaku Co., Ltd.)

C.l. Fluorescent Brightening agent l28 Hiltamine Arctic White DML (Trade name, made by the Hilton-Davis Chemical C0.)

C1. Fluorescent Brightening Agent Calcofluor White LD (Trade name, made by American Cyanamid Co.)

These fluorescent brightening agents are commercially available are to be added in an amount of from about 0.0l to about 1.0 g, preferably, from about 0.05 g to about 0.5 g, per l0 g of the polyvinyl butyral.

Examples of Bluing dye which can be used in this invention are as follows:

The amount of the bluing agent which can be present generally ranges from about 0.01 to 0.5 percent by weight of polyolefm.

The degree of polymerization of the polyvinyl butyral generally ranges from about 200 to about 1,500, and the degree of butyration thereof is about 57 to about 70 mol percent. Polyvinyl butyral is sold under the trade names of Denka Butyral (made by DENKI KAGAKU KOGYO KABUSHIKI KAISHA), Esleck (made by Sekisui Chemical Co., Ltd.) Butacite (made by E. l. du- Pont de Nemours Co.), Mowital (made by Farbwerke Hoechst A.G.), Saflex (made by Monsanto Chem), etc. and can be easily obtained commercially.

The specific characteristics of some of the commercially available polyvinyl butyrals are as follows.

Denka Butyral 2000-] (Trade name, made by DENKl. KAGAKU KOGYO- KABUSHIKI KAISHA) Viscosit Composition (cps. ethanol] PVB toluene PVA, PVAC, Free on) wt. wt. Wt. M01 acid, Trade name 20 C. Appearance SG percent percent percent percent percent Denka Butyral 20001 20=1=10 1.1 223:1 a0 73 63:5:3 01 Doukn Butyral 2000-2 40:50 1.1 22=|=2 3. 0 73 0. 1 Dcnku Butyral 3000-1 (iOilO 1.1 20=|=2 3.0 75 0513 01 Denka Butyral 3000-2 805:10 white m 1.1 201:2 3.'0 75 65=i:3 0.1 DenkaButy1'11l3000-3... 100*10 g 1.1 20:1:2 a.0 75 055:3 01 Denka Butyral 3000-4 1255: 1. 1 :!z2 3. 0 75 65;l;3 0 1 DGIlkll. Butyral 4000-1 105*20 1.1 20:1:2 a.0 75v 055:3 0.1 Denka Butyral 4000-2 210510 1.1 20:1:2 a.0 75 655:3 0.1

No'rE.S(i is specific gravity. 7

Degree of Remaining 15 Kayalight B (Trade name, made by Nippon Kayaku acetal acetyl C Ltd I 5 8 formation group Water (mol (mol content Methanol 1,0 Trade name percent) percent) Viscosity (percent) r1 kBLl 005:3 3 10-30 3 Example I gggIIIII 2g (l) Coating of the Polyethylene Layer. g gg BLS I 67% 3 10:30 2 20 A low density polyethylene (Sum1kathene L-402, Fslccl]: 11% 05: 3 00-100 3 made by the Sum1tomo Chem1calCo., Ltd.) contammg 2 151: 3 i 28388 2% 12 percent by weight of titanium white Taipake R-820, gfi f 2:2 ggjgg made by lshihara Sangyo Kaish a, Ltd.) was coated on 100: is 50 33 2 a paper base (120 g/m m welght and 0.125 mm 1n I 6&2 2 2004,00 2 thickness) using an extrusion method so that the poly- Eslflk 68 3 4004500 3 ethylene was coated in a thickness of 0.045 mm. The No'rE.-Denku B tyral is a trade name of the Denki Kagaku Kogyo extrusion coating machine employed had a 60 mm Kabushikl Knisha. d d T Esleck lsatrade name of the Selnsui Chemical Co., Ltd. yp q er an yp dle of 500 mm m Viscosity of 1311-1 to BH-3 was measured using a Htipler viscometer Wldth- The coa mg rate was The casting h 0.0 in.00::0.1 0.220.120011520000020 .500.23.32. 5. :13 30 roll with a smoothly finished was used, The wtiwrwn in t n l/ n sg i at 0391 90 0 59 9 2 9- face of the resulting polyethylene-coated layer was subjected to a corona dischar e at a electrode a of 8 mm g g P The "W of mvemlon ls Wafer Proof and the and at 250W using a corona dlscharge apparatus made surface thereof is smooth and has a high degree of lusby h L l Hi h Frequency Laboratories ter and a high whiteness. co(U.S.A.).

Therefore, positive prints obtained using the image- 2) Coating of the Polyvinyl Butyral Layer. receiving material wherein the support of this mvention l i having the following composition was is used are not Stained y developer at the g coated on the polyethylene layer of the polyethylene- P thereon f h whlten es and an Q." laminated paperprepared in (1) above so that the solucellent image quality with llttle 1rregular1t1es and with 40 i was coated thereon i a hi k f 0003- m a luster of a high degree. In addition, since the support aft d i of the invention does not lose the hydrophilicity of the Denka butyra] 20 0- (Trade name made by DENKI surface thereof on aging, coa the image: 7 KAGAKU KOGYO KABUS-HIKI KAISHA) g receiving layer thereon may be conductedawhile after K li h 3 (Trade name, made by Nippon Kayak the production of the supp rt. H .5 C Ltd.) g g 1 2 Accordingly, the supply and demand of the support .M h fl- L0 are facilitated in the production of the image-receiving Example 2 material: I (l) Coating of the Polyethylene Layer. Next, to speclfically descllbe f effects of The coating of the polyethylene layer was conducted the invention 1n greater detail a comparison example 5 in the same manner as'described in Example L for reference and several examples of the invention are (2) C ati of the Polyvinyl Butyral Layer. descllbefi below- The procedure described in Example 1 was concompanson Example h ducted using a solution having the following composi- (l) Coating of Cellulose Diacetate. 55

A solution having the following compositions was coated on a paper base so that the thickness thereof Denka Butyral 0- (Trade name, made y after d i was 0,003 Leucophor DC (Trade name, made by Sandoz Ltd.) Cellulose Diacetate (made by Daicel Ltd.) v 12 g 1.5 g, Methanol 30 cc Methylene Chloride 270 cc (2) Coating of Polyvinyl Butyral. Example 3 A solution having the following composition was (1) Coating of the Polyethylene Layer. coated on the cellulose diacetate layer obtained in (l) The coating of the polyethylene layer was conducted above so that the thickness thereof after drying was in the same manner as described in Example 1.

(2) Coating of Polyvinyl Butyral Layer.

The procedure described in Example 1 was conducted using a solution having the following composition.

All of the supports thus obtained had a high whiteness and a specular gloss. Especially, a high degree of luster of the surface, which has heretofore been obtained only by passing conventional supports having a cellulose acetate layer and a polyvinyl butyral layer on a paper base (described in the Comparison Example) through a super calender once or more times, can easily be obtained in the case of the support obtained by this invention without any special treatment such as super calendering. In order to show this fact, the degree of gloss of each of the samples was measured. The results are as follows. The degree of luster was measured by the so-called specular gloss method, that is, the place to be measured was exposed to a parallel light at a given angle of incidence and the reflection intensity thereof in the direction of regular reflection was measured.

The degree of luster was determined using the following formula.

Intensity of the regularly reflected light Intensity of the X100 incident light; 7

Degree of luster percent The gloss meter used was calibrated using a black standard plate (1.5275 in reflective index) as a standard sample.

Sample Degree of Luster (measured The data shown in the table above were obtained using a GM-3M type glossmeter (made by the Murakami Color Research Laboratory).

The hydrophilicity of a conventional polyolefinlaminated paper whose surface was made hydrophilic using a corona discharge treatment decreased with aging of about one month after the corona discharge and, as the result, coating of an image-receiving layer thereon became difficult, whereas, the hydrophilic properties of the support obtained in the aforesaid examples was not deteriorated after several months aging. in addition, the support obtained in the foregoing examples had a whiteness which was higher than that obtained using a polyolefln-laminated paper.

An image-receiving material can be prepared using a support obtained as in the foregoing examples, for example, as follows.

(I) Coating of the Image-receiving Layer.

A dispersion having the following composition was coated on a support obtained as in the foregoing examples so that it was coated in a thickness of 0.0005 mm after drying.

Colloidal Silica (Sold under the trade name of Snowtex C, made by the Nissan Chemicals Industries Co., Ltd.) 50 cc Cadmium Acetate 2H O (2 wt percent aqueous solution) 4cc Lead Acetate 3H O (2 wt percent aqueous solution) 4.

Zinc Acetate 61-120 (5 wt percent aqueous solution) 4cc Sodium Sulfide; 9H O (1 wt percent aqueous solution) 2.4 cc Distilled Water 200 cc Saponin (6 wt percent aqueous solution) 2.6 cc

(2) Coating of the Stripping Layer.

A solution having the following composition was coated on the image-receiving layer at a coverage of 20 cc/m.

Snowtex C 4 cc Dimethylhydanmin/Formaldehyde Condensation Product (mean molecular weight of 320) 4 g Distilled Water 200 cc Saponin (6 wt percent aqueous solution) 3 cc The exposed negative layer was superposed on the image-receiving material, and a developer was spread therebetween for treatment for a definite time. Thereafter, these two materials were stripped from each other and, at this time, the stripping layer provided prevented the developer from remaining on the surface of the image-receiving material. In this place, the layer to be used for such purpose is referred to as a stripping layer.

The image-receiving layer thus obtained is superposed on an exposed negative material which is a Neopan SSS sheet film (Trade name, made by the Fuji Photo Film Co., Ltd., in which a silver bromiodide emulsion is used), and a developer for the diffusion transfer process having the following composition is spread therebetween.

Water 1,860 g Sodium Salt of Carboxymethyl Cellulose l 17 g Sodium Sulflte anhydrous) 78 g Sodium Hydroxide 74.6 g Sodium Thiosulfate (crystal 14.5 g Citric Acid 38.5 g Hydroquinone 52 g The two layers were stripped from each other after 15 seconds and a positive image of an excellentquality was obtained. That is, the positive image obtained had little irregularlities and had beautiful luster, and was not stained by the processing solution. The whiteness in the high light portion thereof was excellent.

What is claimed is:

l. A support for an image-receiving material for the silver salt diffusion transfer process having on a paper base, in order, a polyolefin resin layer and a polyvinyl butyral layer containing a fluorescent brightening agent.

2. The support as claimed in claim 1, in which said polyolefin is polyethylene or polypropylene.

3. The support as claimed in claim 1, in which said fluorescent brightening agent is C.l. fluorescent Brightening Agent 4, 57, 69, 70, 72, 73, 76, 91, 128 or 130.

4. The support as claimed in claim 1, in which said fluorescent brightening agent is present at a level ranging from about 0.01 to about 1.0 per 10 g of said polyvinylbutyral.

5. The support as claimed in claim 1, in which the thickness of. said polyolefin layer ranges from about 5 microns to about 0.1 mm and the thickness of said polyvinyl butyral layer ranges from about 0.5 micron to about 0.05 mm.

6. The support as claimed in claim 1, in which said polyvinyl butyral has a degree of polymerization of from about 200 to about 1,500 and a degree of butyration of from about 57 to about mole percent.

3,776,761 9 10 7. The support as claimed in claim 1, in which said pigment is at least one selected from the group consistpolyolefin resin layer additionally contains a white piging of titanium dioxide, zinc oxide, zinc sulfide and lithment, or a bluing dye. opone.

8. The support as claimed in claim 7, in which said 

2. The support as claimed in claim 1, in which said polyolefin is polyethylene or polypropylene.
 3. The support as claimed in claim 1, in which said fluorescent brightening agent is C.I. fluorescent Brightening Agent 4, 57, 69, 70, 72, 73, 76, 91, 128 or
 130. 4. The support as claimeD in claim 1, in which said fluorescent brightening agent is present at a level ranging from about 0.01 to about 1.0 per 10 g of said polyvinylbutyral.
 5. The support as claimed in claim 1, in which the thickness of said polyolefin layer ranges from about 5 microns to about 0.1 mm and the thickness of said polyvinyl butyral layer ranges from about 0.5 micron to about 0.05 mm.
 6. The support as claimed in claim 1, in which said polyvinyl butyral has a degree of polymerization of from about 200 to about 1,500 and a degree of butyration of from about 57 to about 70 mole percent.
 7. The support as claimed in claim 1, in which said polyolefin resin layer additionally contains a white pigment, or a bluing dye.
 8. The support as claimed in claim 7, in which said pigment is at least one selected from the group consisting of titanium dioxide, zinc oxide, zinc sulfide and lithopone. 